1. Field of the Invention
The present invention relates to an in-pipe inspection robot and, more particularly, to an in-pipe inspection robot, which is inserted into a pipe, to which it is difficult for a worker to gain direct access, and freely moves in the pipe to inspect any damage to a wall of the pipe, any misalignment of a pipe joint, etc.
2. Description of the Related Art
Pipelines buried underground to make water and sewage pipes, electrical lines, communication lines, etc. deteriorate as time passes after construction and require repair or replacement. In particular, in the case of a pipeline where electrical lines or communication lines are wired, it is necessary to replace the electrical lines or communication lines with new ones when their durability reaches zero. However, when a wall of the pipeline is damaged or joint of the pipeline is misaligned, it is difficult to insert the new lines, and thus it is necessary to repair the damaged pipeline before the insertion of the lines.
As a method of repairing the pipeline, a conventional trench repair method has many problems. That is, it is costly and time-consuming to excavate and repave the ground under which pipelines are buried, and during the construction, traffic jam occurs around the construction site, and contamination occurs due to soil and dust. Accordingly, a trench less method of inspecting suspected areas in the pipeline by inserting a robot into the pipeline without excavating the ground has recently been used.
A typical robot used in the trenchless method includes a wheel-type robot disclosed in Korean Patent Publication No. 2010-0094824 and a robot having a structure in which a camera, a repair tool, etc, are mounted on a body provided with a caterpillar crawler, but no concrete examples were given. This type of robot is controlled by an external control unit to move to photograph the internal state of the pipeline, transmit images, and repair damaged areas found, thus performing repair operations.
However, the above-described conventional wheel-type or caterpillar crawler-type in-pipe inspection robots are suitable for the inspection of pipelines which are buried horizontally but cannot run in a pipeline which is installed vertically or obliquely. To solve this problem, a robot based on an inchworm motion has been proposed. However, the conventional inchworm-type robot is difficult to move in a pipeline with curved sections such as curves, T-shaped, Y-shaped branches, etc., and thus its use is limited.